Buggy code:
public class ScheduleFragment extends Fragment implements WeekViewModified . EventClickListener , WeekViewModified . EventLongPressListener , WeekViewModified . MonthChangeListener { public static final String TAG = "ScheduleFragment" ; public static final String EVENT_PIN = "eventPin" ; public static final String LOCATION_PIN = "locationPin" ; private View mScheduleFragView ; private WeekViewModified mWeekView ; private LinearLayout mScheduleContainer ; private ParseUser mUser ; private List < WeekViewEvent > finalWeekViewEvents ; private List < Event > finalEvents ; private boolean firstRun = true ; private boolean eventDetailsOpen = false ; private boolean hasInternet = false ; private EventDetailsFragment eventDetailsFragment ; @ Override public void onCreate ( Bundle savedInstanceState ) { } @ Override public View onCreateView ( final LayoutInflater inflater , final ViewGroup container , Bundle savedInstanceState ) { } private void setUpWeekView ( ) { } private void getLocalEvents ( final int newMonth ) { } private void getRemoteEvents ( final int newMonth ) { if ( hasInternet ) { ParseQuery < Location > locQuery = ParseQuery . getQuery ( "Location" ) ; locQuery . findInBackground ( new com . parse . FindCallback < Location > ( ) { public void done ( List < Location > locList , ParseException f ) { if ( f == null ) { ParseObject . unpinAllInBackground ( ScheduleFragment . LOCATION_PIN , locList ) ; ParseObject . pinAllInBackground ( ScheduleFragment . LOCATION_PIN , locList ) ; Log . d ( ScheduleFragment . TAG , ( ( locList . size ( ) ) + "<seq2seq4repair_space>locations" ) ) ; } else { Toast . makeText ( getActivity ( ) , "No<seq2seq4repair_space>locations<seq2seq4repair_space>found." , LENGTH_SHORT ) . show ( ) ; } } } ) ; ParseQuery < Event > query = ParseQuery . getQuery ( "Event" ) ; query . include ( "category" ) ; query . include ( "host" ) ; query . include ( "location" ) ; query . findInBackground ( new com . parse . FindCallback < Event > ( ) { public void done ( List < Event > eventList , ParseException e ) { if ( e == null ) { <START_BUG> ParseObject . unpinAllInBackground ( ScheduleFragment . EVENT_PIN , eventList ) ; <END_BUG> ParseObject . pinAllInBackground ( ScheduleFragment . EVENT_PIN , eventList ) ; Log . d ( ScheduleFragment . TAG , ( ( eventList . size ( ) ) + "<seq2seq4repair_space>events" ) ) ; createEvents ( eventList , newMonth ) ; } else { Toast . makeText ( getActivity ( ) , "No<seq2seq4repair_space>events<seq2seq4repair_space>found." , LENGTH_SHORT ) . show ( ) ; } } } ) ; } else { showNoInternetDialog ( ) ; } } public void createEvents ( List < Event > eventList , int newMonth ) { } @ Override public void onEventClick ( WeekViewEvent event , RectF eventRect ) { } @ Override public void onEventLongPress ( WeekViewEvent event , RectF eventRect ) { } @ Override public List < WeekViewEvent > onMonthChange ( int newYear , int newMonth ) { } public void scheduleFragmentClick ( View v ) { } public void refreshEvents ( ) { } public void closeEventDetails ( ) { } @ Override public void onCreateOptionsMenu ( Menu menu , MenuInflater inflater ) { } @ Override public boolean onOptionsItemSelected ( MenuItem item ) { } public boolean checkInternet ( ) { } private void showNoInternetDialog ( ) { } }

Fix:
ParseObject . unpinAllInBackground ( ScheduleFragment . EVENT_PIN , finalEvents ) ;